It could be too much pressure. My first thought is too much pump pressure, but if you are sure you have only 4 psi and you didn't do anything else you're not saying, then on to the back pressure thought. First thing to always do when you have a theory, is test it in a fool proof way. All I can think of right now is take the return hose off, plug it so gas doesn't leak from tank, put another hose on pump and run into a gas can and see if relieving the back pressure stops the carb leak. If it did'nt leak before with a mechanical pump you know it's the electric pump. Why the hell do you want an electric? they are for fuel injection and blowers and huge carbs. What carb do you have? If it's a Quadrajet or equivalent, it wants 5 1/2 to 6 lbs. Put the mechanical back on. You need to tell us the engine, the vehicle and the carb. When you ask for help, always tell what you have. Since you are new, you're forgiven. I don't know what "float bowl adjustment to 2 1/4" means. Never heard of 2 1/4 inches, the whole bowl section isn't that deep? Are you talking idle screw turns? BTW I am not very up on electric pumps so........Good luck Atkins. Bartamos.
Last edited by bartamos; 05/27/2010 10:31 PM.
